If the server is started with --port-open-timeout=# 
retry to bind the TCP port if it fails with EADDRINUSE.
Use the new option in mysql-test-run.sh.


mysql-test/mysql-test-run.sh:
  Bug#15591 Occasional test suite abort due to port in use
  Use the new option --port-open-timeout=# for server starts.
  This should fix occasionally late closed TCP ports.
sql/mysqld.cc:
  Bug#15591 Occasional test suite abort due to port in use
  If the server is started with --port-open-timeout=# 
  retry to bind the TCP port if it fails with EADDRINUSE.